Imaging paediatric blunt abdominal trauma in the emergency department: ultrasound versus computed tomography

To determine whether an abdominal ultrasound scan performed by paediatric radiologists is effective in the diagnosis of abdominal injuries in children.

A retrospective cohort study was undertaken of all children who presented with blunt abdominal trauma to a paediatric teaching hospital (RHSC) over a 5-year period between 1 January 2001 and 31 December 2005. Hospital notes and radiology computer systems were interrogated and data were collected and analysed.

Of the 80 children with blunt abdominal trauma, 56 (70%) had abdominal imaging and 23 (30%) had no imaging. Of the 56 imaged, 48 (86%) had an USS of which 25 (52%) were positive (16 demonstrated solid organ injury, 8 free fluid and 1 suspected bladder rupture); 3 of these went on to have a CT scan. 23 had a normal USS; 2 of these children went on to have a CT scan because of a high index of suspicion for small bowel perforation due to their mechanism of injury and clinical signs. Both of these CT scans were normal. Eight children (14%) had a CT scan as the primary investigation, 6 of which (75%) were positive (5 demonstrated liver lacerations and 1 free fluid with no obvious source). All these abnormalities were demonstrated on follow-up USS. 23 children had no abdominal imaging and once their symptoms and signs had settled they were safely discharged home.

Abdominal USS performed by paediatric radiologists is an accurate method of assessing abdominal injuries. However, CT scanning can assess certain abnormalities such as pancreatic or duodenal injuries and small amounts of free intraperitoneal air more accurately. The importance of serial clinical examination must not be overlooked.